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Burned CDs Last 5 years Max -- Use Tape?
Lam1969 writes "Computerworld has interviewed Kurt Gerecke, an IBM storage expert and physicist who claims burned CDs only have a two to five-year lifespan, depending on the quality of the CD. From the article: "The problem is material degradation. Optical discs commonly used for burning, such as CD-R and CD-RW, have a recording surface consisting of a layer of dye that can be modified by heat to store data. The degradation process can result in the data 'shifting' on the surface and thus becoming unreadable to the laser beam." Gerecke recommends magnetic tapes to store pictures, videos and songs."
I have some CDs that are burned copies (although I'd call this great quality cds, not cheap storebrand with no backing), stored in a CD wallet case that are easily over 5 years old... still work great.
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Magnetic tape? Ok
Anyone know where I can download an MP3 jukebox for my Vic 20?
Those are records. I don't know about you, but I don't have an LP-ROM drive.
Haven't other studies confirmed much longer lifetimes in the past for CD-R? After all, we've had CD burners for longer than 2-5 years. Is this only a surprise because absolutely nobody has ever gone back and tried to read an old disc? Somehow I'm still doubtful of his conclusions.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
I have CDs that have lasted 10 years with no errors. Obviously 5 years is not the maximum life. Perhaps the maximum EXPECTED life.
We've known that CD-Rs will degrade for a long time. Hispace have recently launched a new range of CD-Rs aimed at digital photographers. These disks use 24 caret gold to help add stability to the disks. As a result, they come with a 100 year warranty.
Your porn will be around for decades after all!!
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The wedding photographer for my wedding gave me a DVD of the video + photos. After about two years the DVDs were so degraded that I could not a single DVD player would recognize them. And that's with light usage... Now I keep important DVD as images on an external hard disk.
When I first asked this question of how long CDs will last, I was told about 70 years.
I was also told that to lengthen a CDs shelf life, always store them vertically in a cool dry place, and clean them from the inside ring to the outer edge in a straight line.
I found an article from the Optical Storage Technology Association and they say it depends on the initial CD quality and handling.
According to this article, unrecorded CDRs last about 5-10 years, manufacturers claim recorded CDRs 50-200 years and recorded CDRWs 20-100 years.
More info: http://www.osta.org/technology/cdqa13.htm
He who knows best knows how little he knows. - Thomas Jefferson
I can't remember all of the details, but I am sure there was a Dutch group who took a sample of all of the available CDs at the time, burnt data onto them, put them in storage for 2 years and then re-tested the disks quality. Their results showed that all of the disks had significant degredation.
.. here is a link to a news report of that study
OK
http://www.cdfreaks.com/news/7751 This link includes a link to the original Dutch article
To quote:
"The tests showed that a number of CD-Rs had become completely unreadable while others could only be read back partially. Data that was recorded 20 months ago had become unreadable. These included discs of well known and lesser known manufacturers."
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The best way to preserve data, imho is storage independent. Suppose you want to archive your family photos. Sure you can put them on a hard drive... then you can use raid, hard drive will be replaced regulary and the probability of a simultaneous failure being low you dramatically increase the lifespan of your storage. The same could be done on the internet with a P2P network dedicated to long term storage. You divide your files into chuncks and calculate a hash. Peers download it and keep it on their machines. You just have to keep signatures of your chuncks, you can do that on highly reliable mediums, like grave it into stone if you wish. The P2P network automatically polls for chunks and ensure redundancy by pushing rare pieces to clients. To ensure collaboration, you can upload only a fraction of what you host. Some sort of bittorrent expect it's rather a bitpool.
\u262D = \u5350
I've mulled this occasionally, but I suspect the late 20th century and early 21st century will become a mini-dark ages (at least for personal or family things).
The reasons for this:
1. depressingly high failure rate of hard disks
2. lack of long term storage media
3. obsolete formats
As for tape, DLTtape (invented for the venerable VAX) is supposed to be able to last 25 years in good condition. How many people buy DLTtape drives? They aren't cheap and the tapes are not cheap. They are about the only thing with the capacity to store all your photos and video on one cartridge.
Digital photos and video seem like great things (and are: I'd hate to have to edit my videos the old fashioned way) but there is a sting in the tail that most people won't expect. If I want to look at a photograph my Dad took in 1972, I just pull it out the draw and look at it. No maintenance has had to be done on that photograph - it's just been stored in a cool, dry, dark place.
Digital data on the other hand needs periodic maintenance. If a format you've used becomes obsolete, you have to go through and update your entire library. You have to periodically back it up. You have to periodically cut it to media like CD. How much family history have people lost already due to dead hard disks, and not realising the need to continuously back up and format shift? Even if a DLTtape cartridge is still intact and readable in 75 years time, will there be anything to read it? Will JPEG decoders come with everyone's device to view photos?
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Not only have the early deaths of CD-Rs been greatly exaggerated before, but even the lifespan of pressed CDs were (are?) hotly disputed. In the early 80's I heard all about how CDs would last forever because each play didn't degrade the quality ever so slightly like it did with cassette tapes and vinyl records. Then in the late 80's a group of researchers determined that CDs would probably only last ten years, for whatever reason.
I got my first CD-RW drive when it was a $700 2x model well over ten years ago. The first things I burned were a bootleg Tragically Hip CD and a few rented Playstation games. I still play that Hip CD and recently I dugg out my Playstation collection to use with the epsxe emulator and they all still work great, though I can't remember which of my burned games were copied when.
I have had a few CDs and DVDs go bad, but they've always been really cheap media. Even cheap CD-Rs have been ok, but I have noticed that cheap DVD-Rs can be very poor quality and sometimes the data won't last through the night. These are usually identifiable because at least half the time the data will be corrupt straight out of the burner. You don't have to spend a lot to get good media, just don't get the cheapest media you can find.
The global economy is a great thing until you feel it locally.
The tape companies, obviously.
Seems that with all the recent cost cutting CD-R manufacturers have been using cheaper materials lately. I have CD-Rs that are like 10 years old and still running strong. However, I have some CD-Rs that I have purchased within the last few months and they are already going bad.
http://www.tradealyst.com/
I just recently tested ~120 cds from about 1999-2002.
Attempting to read them with a DVD drive failed many discs.
But reading with a CD drive I was able to read all of them (after some cleaning) except two (most files were readable) that were scratched.
It seem there is some difference between DVD and CD drives.
Most CDs were burned with 2-8x speed, I almost never use >16x today.
The concern I have is whether I had a working drive to read the tapes with in 40 years.. Oh, nevermind, I'm 60 now, so that probably won't be a problem for me personally..
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
For most personal users one DVD will fit everything they need. If they have a big photo collection maybe re-burn all DVDs yearly.
I used to backup to CDROM. Now I back up to DVD. I'm sure something else will come out in the future.
Isn't the cost point close enough yet to just use hard drives instead for long term storage and not be too bad?
You can pick up OEM 250GB hard drives for around $100. Toss in a $50 USB case or a SATA case and you're looking at $1.67 a GB storage. Plus you're not limited to 4.5GB file size.
Sure drives fail but you won't be spinning them that often. I'm begining to think it may be worth it for the long term. Then use the USB drive or SATA as needed and if need be burn a disk.
This guy has one. There's even a few pics linked at the bottom of the page. Perhaps he'll let you borrow it.
Be a real patriot: Question authority. Think for yourself. Formulate your own conclusions.
NIST Did a study that shows up to 30+ years of longevity that is totally dependant on handling and storage.
Yeah, except that seek time would really suck -- no matter how quickly you could pick up and move the tonearm.
Great. I lose hundreds of precious photos. They give me a buck.
"I'd rather be a lightning rod than a seismometer." -Ken Kesey
Finally, some have claimed that the glue on the sticky labels might affect the longevity of the dye in the disc, presumably by leaching through the thin top coating of polymer. Search for "glue" in that story, it's half way down or so.
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Most serious photographers I know re-burn their archives every one or two years.
I have always viewed any burnable optical disc as a short-term disposable item - I never seriously considered them as a safe medium for long-term archival storage. Up to the recent past, I would have agreeed with the recommendation that magnetic tape is a better long-term medium....but then I ran into the problem of trying to make an ancient tape drive work. These days, I use good old-fashioned IDE (PATA) hard drives in external IDE-to-USB2/FireWire enclosures for archival storage. The problem of the bearings wearing out doesn't happen if the drive isn't on. As long as it's stored in appropriate environmental conditions - it'll last > 100 years. I have a couple of them that I rotate offsite every two weeks, so one copy is at home and another is at the office. Simple, cheap and very reliable.
... I like to keep an open mind, but not so open that my brains fall out. - Judge Harry Stone, Night Court
That's a well known idea, I was going to put here some samples of the distributed backup in action but only can find when Cringely talked about the very same concept.
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The article says to use magnetic tape because the CDs degrade.
So does tape. Unless you're the BOfH, in which case you have a tape safe. But you can't use that to store tapes - its not climate controlled, and you've got too many bodies hidden in it anyway ... but ever tried to read a 10-year-od tape on a new machine? I gave up - it was easier to connect to a serial port and just dump the whole database over the course of a week, its that bad. Then another day for updates. Todays USB and Firewire will be the next generation's serial ports.
So, use a hard drive?
Leave it sitting on a shelf too long and you get "stiction" - so that's no good either. And have you even TRIED to access a 10-year-old drive in todays machines? The bois tries to auto-config, and the machine won't boot.
Zip disks? Hahahah click of death hahahah (I've got several zip drives that are "unzipped")
Paper printouts? Well, those are good for a few decades, but not exactly portable ... anyone care to figure out how many acres of trees a hex dump of a 200-gig drive will take?
Nope, stone tablets - to hit anyone over the head with who thinks that there's any real long-term solution other than to just re-copy to the latest format and pray.
Don't buy name brand media. They're just rebranding, and they can switch suppliers on you.
Go right to the asian source, buy from a reputable importer. I use supermediastore.com, and I buy nothing but Taiyo Yuiden media.
The place where I work has a high-speed multispindle CD-R duplication station, and goes through CD-Rs by the thousands per month. I asked a while ago and they have tried everything, and now use NOTHING but Taiyo Yuiden media also. If they have a failure, we have to ship a replacement overnight; so a single disc failure, by the time you count all the people who have to handle a complaint and the postage, can easily cost $50, so they buy what WORKS.
Have your army of minions engrave all your really important data on clay tablets. Then try to make sure the tablets are stored in the basement of your palace when it burns to the ground, so the clay gets well-fired. Thousands of years from now, archaeologists will marvel at your beautifully preserved backups. They'll call it "cuneiporn."
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
Tapes? Tape drives? Someone is trying to sell a stock of old drives, I'll bet. My $1,300 Seagate tape drive and expensive tapes were very unreliable compared to CDs and DVDs.
CDs and DVDs stored in ziplock bags seem to last a long time.
Changes in atmosperic pressure cause other methods of storage to breathe. Eventually pollution enters. Ziplock bags don't breathe, they just expand and contract as the weather changes.
Sorry, you just reminded me of the History of Life Part I, where Moses comes out with the Fifteen Commandments... Oops, Ten Commandments...
This thread also strikes me as funny because I'm in the middle of archiving about 800 VHS tapes to DVD. Many are 15-20 years old, and I've been surprised at how well most of them still work. I wonder if the DVDs will last as long, but I figure it'll be easier to move the data off them since it won't have to be done in real time.
Besides, it's more of a space issue at this point. Which I'm guessing would be an issue with the stone tablets too!
The revolution will NOT be televised.
That has to be the most pretentious fucking website I have ever seen.
SMALL TEXT NO GRAPHICS LOTS OF RANDOM PARENTHETICAL STATEMENTS USAGE OF FAKE WORDS OMFG I'M SO COOL
"stop. unchain. (chain reaction)"
I only have one thing to say about this. The last line.
+++ATH0
I have never had a failure on one of my archive disks going back to 1997. But I keep these in individual cases stored vertically etc...
Stuff that is not replacable (my personal photos) I burn on two different disk types. I always use high quality disks. Using Fuji TY dvd R+ right now. I believe DVD R disks are a bit more rugged than CD R.
My car disks live in my car in Ottawa Canada. Brutal humid hot summers, I have a set of CD-r in a visor holder. Most of these disks have been in the car for 5 straight years. When I park a disk in my player it often stays for a week at a time. My CD player ejects disks so hot you don't want to touch them. Here I have a few skippers, but each one that skips is also skratched to pieces. Either way. 5 years of torture and most are still fine. I don't think any skip that are not scratched up.
I feel pretty secure about my well cared for indoor disks lasting ten years. Though I will start moving my CD-R backups to DVD.
In ten years, terrabyte storage should be common and cheap.
There's a correct procedure to follow, so that CDs can be used for long time storage. CDs can be successfully used to store data, even though they're so fragile. It's just necessary to do a lot of maintenance. Don't ask me about the details, I'm just writing here what I remember about this.
:= CD2 and CD2 := CD3.
1) Burn 2 identical CD-Rs
2) Store them inside some protected place, upright
3) When it's necessary to use them, use just CD1. CD2 is never used.
4) After n years, throw away CD1. (Since the guy said it takes 5 years for the CD to stop working, n should be 2.5 or less, depending on how much you use CD1). Burn CD3. Let CD1
5) Goto 2.
This is a very cheap way to store data.
hanging chads?
Lump lingered last in line for brains, and the ones she got were sorta rotten and insane.
The problem is that pressing your own CDs is not cost effective in any way. It only becomes cost effective once you print many (1000 or more) identical discs. The costs per CD go down as you do more identical discs. Setting up the platter to stamp out just one disc would be extremely expensive, as well as very time consuming.
I was thinking more along the lines of someone inventing, or streamlining the process to make it cheaper.
For instance. Currently we're using lasers to burn out reflective pits on metallic dyes adhered to plastic discs.
For pressed CDs, we're not using dyes, but some metallic compound that is physically pressed into pits.
My idea would be to have the same or similar metallic compound as pressed disc, only use a stronger laser to burn out physical pits. This could be a commercial grade device used in professional shops and not for the average home consumer. Something like this could be viable could it not?
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Do not look into laser with remaining eye.
The problem is that the whole concept of arhival storage is no longer workable in the "digital age". Non-electronic media doesn't have enough capacity to store the volume of data we generate today, and electronic media are constantly becoming obsolete. The solution is to give up trying to "archive" data. Just keep it live. Most people upgrade their computer(s) every few years, and each time they upgrade their data storage to a newer system and/or higher capacity. Hard disks are big enough today to store most people's entire data collection, and capacity is growing exponentially. So just keep all your data on a live disk (or disks), back it up regularly on another hard disk, and copy both to new media when you upgrade your computer. Your data will never die.
I don't know about you guys, but my data always feels "warmer" when I read it from an LP-ROM. I can't explain it any better than that, you can just FEEL it, man! CDs are cold and digital, there's no love there.. Look, all I'm saying is that when I'm in the mood for some soulful gaming I bust out my copy of Quake4 on vinyl, none of this crap you'll find on CD (or worse, DVD) feels RIGHT, MAN!! VINYL FOREVER!!11 DEATH TO THE OPTICAL OPPRESSORS!!1111
"Bother," said Pooh, as lightning knocked out hi%#&(F*@NO CARRIER
Great - so how am I supposed to even load those monstrosities into my thumbchip 'puter in 30 years? p Especially since all optical lasers will have been banned as potention "terr'rist weapons" under the laws passed by Emporer Bush the First in 2016?
Gold reflective layer CD-R's with a stabilized pthalocyanine dye have an expected shelf life of 200 years.
That's 4 times longer than the expected life of an aluminum reflective layer pressed CD.
Education is a better safeguard of liberty than a standing army.
Edward Everett (1794 - 1865)
I was thinking about this recently. The problem is that you need a really higth power laser to create a medium that lasts. If the material is inert (the nearer that I can think about are gold and glass, preferably glass), the degradation time will decrease exponentialy with the laser power*. That is good, but even then, you'll need a very powerful laser.
Things can go better if you use some kind of revelation process, like films. Then you can create higth energy recordings with a low energy laser and a chemical reaction. The problem is that inert media don't sufer chemical reactions easily, that is by definition. Other alternative is using a mechanical process. Mechanical processes with the power required to make your media last a very long time are easy to engineer, but they are not very precise. So, we end up with a low density medium.
The only thing I can see how to create a long lasting medium with is eletrical fuses. I think it is possible to design a hight density PROM chip with this characteristic, but I never saw one.
* The odds of any process happenning that will destroy your data decreases exponentialy with the energy that this process needs to happen. That is, if you use an inert material.
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